Look at solana base branch

Author: LucasSte

src/build_helper/src/git.rs

@@ -87,7 +87,7 @@ pub fn updated_master_branch(
 ) -> Result<String, String> {
     let upstream_remote = get_rust_lang_rust_remote(config, git_dir)?;
     let branch = config.nightly_branch;
-    for upstream_master in [format!("{upstream_remote}/{branch}"), format!("origin/{branch}")] {
+    for upstream_master in [format!("{upstream_remote}/{branch}"), format!("origin/{branch}"), "origin/solana-1.84.1".to_string()] {
         if rev_exists(&upstream_master, git_dir)? {
             return Ok(upstream_master);
         }